1. Field of the Invention
This invention relates to a cam grinding machine for shaping cams into predetermined profiles.
2. Description of the Prior Art
The cam shafts which are employed as engine parts are provided with plural numbers of intake cams and exhaust cams in alternate positions. These cams are usually ground to predeterimed profiles by means of a cam grinding machine which is arranged to jiggle the cam shaft relative to a grinding wheel according to the contours of master cams.
The intake and exhaust cams on a cam shaft of this sort have different shapes, so that, if they are ground by the same machining cycle, profile errors occur to the intake and exhaust cams in different degrees. As a result, there arises a problem that one type of cam is unacceptable in accuracy while the other type of cam is acceptable. In a case where the machining cycle is changed, prolonging the spark-out time to hold the cams of the other type within a required tolerance, there will arise another problem that the machining time for each cam shaft becomes too long.